Urinary System

Urinary Tract Calculi Dialysis Movement of fluid/molecules across a semipermeable membrane from one compartment to another Used to correct fluid/electrolyte imbalances and to remove waste products in renal failure Treat drug overdoses Begun when patients uremia can no longer be adequately managed conservatively Initiated when GFR (or creatinine clearance) is less than 15 mL/min Dialysis Two methods of dialysis available Peritoneal dialysis (PD) Hemodialysis (HD) ESKD treated with dialysis because There is a lack of donated organs Some patients are physically or mentally unsuitable for transplantation Some patients do not want transplants Osmosis and Diffusion across Semipermeable Membrane Peritoneal Dialysis Peritoneal access is obtained by inserting a catheter through the anterior abdominal wall Technique for catheter placement varies Usually done via surgery Tenckhoff Catheter Waiting period of 7 to 14 days preferable Two to 4 weeks after implantation, exit site should be clean, dry, and free of redness/tenderness Once site healed, patient may shower and pat dry Dialysis Solutions and Cycles Available in 1- or 2-L plastic bags with glucose concentrations of 1.5%, 2.5%, and 4.25% Electrolyte composition similar to that of plasma Solution warmed to body temperature Three phases of PD cycle Inflow (fill) Dwell (equilibration) Drain Called an exchange Inflow Prescribed amount of solution infused through established catheter over about 10 minutes After solution infused, inflow clamp closed to prevent air from entering tubing Dwell Also known as equilibration Diffusion and osmosis occur between patients blood and peritoneal cavity Duration of time varies, depending on method Drain Lasts 15 to 30 minutes May be facilitated by gently massaging abdomen or changing position Complications Exit site infection Peritonitis Hernias Lower back problems Bleeding Pulmonary complications Protein loss Effectiveness and Adaptation Short training program Independence Ease of traveling Fewer dietary restrictions Greater mobility than with HD Hemodialysis Obtaining vascular access is one of most difficult problems Types of access Arteriovenous fistulas and grafts Temporary vascular access Vascular Access for Hemodialysis Dialyzers Long plastic cartridges that contain thousands of parallel hollow tubes or fibers Fibers are semipermeable membranes Hemodialysis Procedure Two needles placed in fistula or graft One needle is placed to pull blood from the circulation to the HD machine The other needle is used to return the dialyzed blood to the patient Components of Hemodialysis Continual Renal Replacement Therapy (CRRT) Alternative or adjunctive method for treating AKI Means by which uremic toxins and fluids are removed Acid-base status/electrolyte balance adjusted slowly and continuously Often used in hemodynamically unstable patients Hemofilter change every 24 to 48 hours Ultrafiltrate should be clear yellow Specimens may be obtained for evaluation Most common approaches: venovenous Continuous venovenous hemofiltration (CVVH) Continuous venovenous hemodialysis (CVVHD) Q&A: A patient undergoes peritoneal dialysis exchanges several times each day. What should the nurse plan to increase in the patients diet?a) Fatb) Proteinc) Caloriesd) Carbohydrates

Kidney Transplantation Very successful One-year graft survival rate Cadaver transplants: 90% Live donor transplants: 95% Advantages of kidney transplantation over dialysis Reverses many of the pathophysiologic changes associated with renal failure Eliminates dependence on dialysis Less expensive than dialysis after the first year Kidney Transplantation Immunosuppressive Therapy Goals Adequately suppress the immune response Maintain sufficient immunity to prevent overwhelming infection Complications Rejection Acute rejection Occurs days to months after transplantation Chronic rejection Process that occurs over months or years and is irreversible Infection CV Disease Malignancies Recurrance of Renal Disease Steriod-Related Complications Q&A: Six days after kidney transplantation from a deceased donor, a patient develops a temperature of 101.2 F (38.5 C), tenderness at the transplant site, and oliguria. The nurse recognizes that these findings indicatea) Acute rejection, which is not uncommon and is usually reversible.b) Hyperacute rejection, which will necessitate removal of the transplanted kidney.c) An infection of the kidney, which can be treated with IV antibiotics.d) The onset of chronic rejection of the kidney with eventual failure of the kidney.

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